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BASELINE RES

Structure dossier · WDID 0604173 · RESERVOIR · BOULDER CREEK · DWR record

Source DWR administrative record · verify at DWR structure ↗ Source DWR administrative record · verify at DWR diversion records ↗ Source Our computation, scored against a reference · scored against DWR's call analysis, see /methods

Where this page's figures come from

Generated 2026-10-12 17:51 by Hydrohistorian. Sources: DWR HydroBase snapshot HydroBase_CO_20260928 (history) + CDSS REST (current), USGS NWIS cross-checks. Engine v0.5.0 (dd58e60) — every figure regenerates from this named code version and data image.

The record and the river

Where this structure is measured

GageFlowing nowRecordHow we know
BASELINE RESERVOIR OUTLET BASOUTCO 0.0 cfs 2022–2026, 1,395 days DWR telemetry mapping

A green link is DWR's own: either its telemetry inventory maps this WDID to that station, or the station is named for this WDID (0700553 → 0700553A). An amber one is ours — the station sits within 250 m and shares a distinctive word with this structure's name, which is a strong hint rather than a DWR statement that this gage meters this structure. Wrong? Tell us.

Flowing now

0.0 cfs as of 2026-10-12 14:15 (3.6 h ago)

Zero is a real reading: the gage is reporting, and it says this structure is not diverting right now.

Provisional 15-minute telemetry from BASOUTCO ↗ (BASELINE RESERVOIR OUTLET). Raw, not the approved record — it is never merged into the diversion history below. DWR publishes the official diversion record after the water year closes and is approved, which is why that record ends months back while this reads minutes ago.

In short

BASELINE RES holds 12 decreed rights on BOULDER CREEK. As of 2026-09-27, 12 of them are out of priority under a call at admin 3744.00000 placed by HOWELL DITCH. 7 further calls state no district and sit outside this one, so they are counted here rather than assumed either way. In a median year over its last 14 recorded years it diverts 3,686 acre-feet. It was a party to 5 court cases that also touched 19 other structures.

Assembled from the figures on this page — every number above is checked against them before it is shown (9 checked). The detail, with its method, is in the cards below.

Download this structure

Everything on this page as data you can work with — and a README that makes it citable: the HydroBase snapshot it was built from, the build commit, what every column means, the method behind each derived figure, and that method's stated limits.

⇩ Full record (.zip) Print / save as PDF

Or one table at a time: rights.csv · annual_use.csv · curtailment_now.csv · court_cases.csv · co_parties.csv · call_climatology.csv

What is in the bundle
  • rights.csv — every decreed right, most senior first, with admin numbers, dates, amounts, uses and case numbers.
  • annual_use.csv — recorded diversion by year, with releases accounted separately.
  • curtailment_now.csv — each right's current priority status and how often it was out across analog years.
  • court_cases.csv — the cases attached to its rights.
  • co_parties.csv — the other structures that were parties to those cases. Not available anywhere else.
  • call_climatology.csv — how often each right has been out of priority by week of season, with confidence intervals and the seasons the record could actually judge.
  • README.txt — provenance, methods, limits, disclaimer, and links back to DWR's own records for verification.

Where it sits

Location as DWR records it (storage). Faint dots are the neighbouring water; click any to open it.

Dam safety

Dam BASELINE - EAST (completed 1905)
Hazard class High
Condition at last inspection Conditionally Satisfactory (2025-03-05)
Storage restriction None on file
Normal storage 5,300 AF
Physical status Active
Emergency action plan Yes

Source: DWR Dam Safety’s jurisdictional-dam inventory (damsafety/damsafetydaminfojd), refreshed weekly. Joined on this structure’s own WDID as DWR records it on the dam. Hazard class describes the consequence of failure, not the likelihood of it. DWR’s dam record.

Current administration

● Fully called out — call at RURAL DITCH (BOULDER CREEK, priority 1862-05-09).

● Fully called out — call at HOWELL DITCH (BOULDER CREEK, priority 1860-04-01).

Which of its rights are out of priority?

Under today's controlling call (HOWELL DITCH, priority 1860-04-01): 12 of this structure's 12 rights are out of priority now. (7 call(s) state no district and sit outside this one — not judged, not assumed.) In the 4 past years most like this one (2024, 2023, 2022, 2025), 12 of the rights shown below were out at least one week in at least one analog year.

Right (priority)NowAnalog years outMajority out by
1872-04-15 8141 ● out 3 of 4 2026-09-27
1873-06-01 8553 ● out 3 of 4 2026-09-27
1881-09-01 11567 ● out 3 of 4 2026-09-27
1884-11-01 12724 ● out 3 of 4 2026-09-27
1892-02-15 15386 ● out 3 of 4 2026-09-27
1897-10-01 17441 ● out 4 of 4 2026-09-27
1904-11-04 20890 ● out 4 of 4 2026-09-27
1906-06-20 20890 ● out 4 of 4 2026-09-27
1922-11-29 26630 ● out 4 of 4 2026-09-27
1915-08-29 27930 ● out 4 of 4 2026-09-27
1929-12-31 29219 ● out 4 of 4 2026-09-27
1935-11-30 31379 ● out 4 of 4 2026-09-27
How this table is built, and what it is not

“Now” compares each right's admin number with today's most senior applicable active call. The outlook uses flows at BASELINE RESERVOIR OUTLET around 2026-09-27 (the newest reading on file) — currently 164% of that gage's own median for this window — to pick the 4 most similar past years with complete administration records (2004–2026). Only calls that verifiably apply count: DWR's own district statements in the call's set comments, a caller located in this district, or — on the same stream, where DWR records both stream miles (measured from the mouth) — a caller DOWNSTREAM of this structure. An upstream senior cannot demand water this diversion never deprives it of. Calls that state nothing and sit elsewhere are counted as unjudged rather than assumed, which also means the verified record is shorter than the raw one: early calls rarely state districts. For each week it finds the most senior call then in force; a right is out in that week exactly when that call is senior to it, which is why one line prices every right and juniors can be out while seniors keep diverting. “Majority out by” is the first week out in more than half the analog years. A frequency among named historical years, not a probability from a model, and not a forecast of what the division engineer will do. It says how often years whose flow resembled this one were under a call senior to this right in a given week. Snowpack, storage, and the actual administrative decisions of a given season are not modelled. Check the analog years listed: if they do not resemble this year to you, the outlook does not either.

Where it sits in line

Priority 1872-04-15 — 90th most senior of the 1867 structures with decreed rights in this water districtDWR's administrative subdivision of a river basin; the unit calls are usually stated in..

Under prior appropriationColorado's rule for sharing water: first in time, first in right. Age decides, not proximity or need., everything ahead of it in this line is satisfied in full before it receives any water. Immediately ahead: GOOSE HAVEN RESERVOIR COMPLEX (1872-04-15). Immediately behind: 0604201 (1872-04-15).

On MAINSTEM at river mile 12.7, it is 17th of 78 down the reach. Immediately upstream: HARPE SPRING. Immediately downstream: BUTTE MILL DITCH.

Position on the modelled network, not a claim about whose water this is — a stream carries water from many rights at once, and diverted water returns to it.

Decreed rights (12)

Admin noDWR's numeric encoding of a water right's seniority. Smaller is more senior; the integer part counts days from 1849-12-31 to the date that ranks the right. AppropriatedWhen water was first put to beneficial use. It sets seniority unless a prior adjudication date is later. AdjudicatedWhen the water court confirmed the right. A use decreed in 1975 was not a decreed use in 1955, however old the appropriation is. AbsoluteA right actually put to use, as opposed to conditional -- a placeholder for a use not yet made. ConditionalA right reserving a place in line for a use not yet made; it must be diligently pursued or it lapses. Alt-pointAn absolute amount decreed at another structure that may be diverted here instead -- an alternate point of diversion or an exchange. DWR calls this the APEX amount; a right showing 0.0 absolute but an alt-point amount is exercised here under another structure's decree. Decreed forWhat the court said this water may be used for -- irrigation, municipal supply, augmentation and so on.Case
8141.00000 1872-04-151882-06-02 0.0 AF 0.0 79.0 AF Irrigation, Municipal +5 85CW0119, W8348
8553.00000 1873-06-011882-06-02 0.0 AF 0.0 250.0 AF Irrigation, Municipal +5 85CW0119, W8348
11567.00000 1881-09-011907-03-13 0.0 AF 0.0 1.5 AF Irrigation, Municipal +4 85CW0119
12724.00000 1884-11-011907-03-13 0.0 AF 0.0 52.5 AF Irrigation, Municipal +4 85CW0119
15386.00000 1892-02-151907-03-13 0.0 AF 0.0 180.2 AF Irrigation, Municipal +4 85CW0119
17441.00000 1897-10-011907-03-13 0.0 AF 0.0 172.2 AF Irrigation, Municipal +4 85CW0119
20890.20031 1904-11-041926-06-21 2981.2 AF 0.0 — Irrigation, Municipal +8 87CW0327, 90CW0108 +7
20890.20624 1906-06-201907-11-03 0.0 AF 0.0 436.3 AF Irrigation, Municipal +4 85CW0119
26630.00000 1922-11-291935-01-09 1672.0 AF 0.0 — Irrigation, Municipal +8 84CW0309, 80CW0451 +7
27930.23981 1915-08-291953-09-28 0.0 AF 0.0 25.0 AF Irrigation, Municipal +4 85CW0119
29219.00000 1929-12-311953-09-28 1395.0 AF 0.0 — Irrigation, Municipal +8 84CW0309, 80CW0468 +7
31379.00000 1935-11-301953-09-28 847.0 AF 0.0 — Irrigation, Municipal +8 97CW0195, CA12111 +7

Amounts marked cfs are flow rates; AF are stored volumes (storage rights are decreed in acre-feet). An absolute amount of 0.0 beside an alt-point amount is not a dead right: the water is decreed at another structure, and that row records permission to divert it here instead (an alternate point or exchange). A case listing several numbers reflects the original decree plus later change cases.

Water-court filings naming this structure

4 applications in the monthly water-court resumes explicitly reference this WDID. The resume is the earliest public notice of a new claim (C.R.S. 37-92-302) — years before anything reaches the decree record below. Most applications name structures by name rather than WDID, so absence here is weak evidence of absence.

MonthCaseWhat it asksOppose byExcerpt
2026-08 2026CW3125 reasonable diligence 2026-10-31 (19d left) CASE NUMBER 2026CW3125 (90CW108) (99CW125) (12CW72) (20CW3017) APPLICATION FOR FINDING OF REASONABLE DILIGENCE IN BOULDER COUNTY . 1. Name, Mailing Address, Phone Number, and E -mail Address of Applicant . CITY OF LAFAYE…
2026-06 2026CW3093 reasonable diligence closed 2026-08-31 CASE NUMBER 20 26CW3093 (05CW295) (19CW3201) APPLICATION FOR FINDING OF REASONABLE DILIGENCE IN BOULDER COUNTY. 1. Name, Mailing Address, Phone Number, and E -mail Address of Applicant . CITY OF LAFAYETTE , c/o Cari Bisc…
2025-10 2025CW3137 reasonable diligence closed 2025-12-31 CASE NUMBER 2025CW3137 (97CW195) (06CW150) (19CW3020) APPLICATION FOR FINDING OF REASONABLE DILIGENCE IN BOULDER COUNTY – 1. Name, Mailing Address, Phone Number, and E-mail Address of Applicant. CITY OF LAFAYETTE, c/o Ca…
2025-04 2025CW3049 reasonable diligence closed 2025-06-30 CASE NUMBER 2025CW3049 (79CW387) (93CW025) (01CW295) (02CW281) (18CW3035) APPLICATION FOR FINDING OF REASONABLE DILIGENCE IN BOULDER COUNTY. – 1. Name, Mailing Address, Phone Number, and E-mail Address of Applicant. CITY…

Source: Judicial Branch combined monthly resumes (archive), indexed nightly; WDIDs attached only when a 7-digit token in the filing matches DWR’s structure inventory.

How often is it out of priority?

Across the 12 seasons whose call record is complete enough to judge this structure (2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025, 2026), week by week from April.

most senior right · admin 8141.00000 · peaks at 12 of 12 seasons
AprMayJunJulAugSep
middle right · admin 20890.20031 · peaks at 12 of 12 seasons
AprMayJunJulAugSep
most junior right · admin 31379.00000 · peaks at 12 of 12 seasons
AprMayJunJulAugSep

Snow sets the clock here. In the driest third of snow years (4 seasons), the call settled in for the season around July 15 (June 3 to July 15 across those years); in 1 of them it never lifted at all. In the middle third (4 seasons), the call settled in for the season around June 24 (June 17 to July 8 across those years); in 1 of them it never lifted at all. In the wettest third (4 seasons), the call settled in for the season around June 24 (June 17 to June 24 across those years); in 2 of them it never lifted at all.

Snow years ranked by the district’s April 1 snow-water percentile across 3 SNOTEL sites; 12 seasons carry both a snow reading and a judgeable call record. How the past played out, not a forecast.

Why only 12 seasons, and what the bars mean

Each bar is one week: how many of those seasons that right was out of priority under a call this site can lawfully attribute to this structure. Green is never, red is every season on record.

The short record is a property of DWR's data, not of the river. A call only counts against a structure when we can establish it applies — by the districts named in its set comments, or by stream mile on the same source. DWR did not begin stating affected districts routinely until about 2015: fewer than one call in ten can be judged before then, against roughly two in three since. A season we cannot judge is not a season without calls, so it is dropped rather than counted as quiet — 11 seasons dropped here.

This is a frequency over past seasons, not a forecast. It says nothing about what the division engineer will do this year.

Recorded use (last 15 years on record)

Years far under the decreed amount? That gap has a name — paper water vs. wet water, explained on this structure.

In a median year this structure has a recorded diversion of 3,686 AF. Its most recent year on record, 2025, came in at 52 AF — 1% of that, and 2nd lowest of the 14 years with a recorded volume.

This structure records both diversions and reservoir releases — they are separate water movements and are accounted separately below.

YearDiverted (AFA volume: one acre covered a foot deep, about 326,000 gallons -- roughly a suburban household's outdoor use for a year.)Compared with its own recordReleased (AF)Days recordedPeak (cfs)
2009 3,809 8th lowest of 14 · 103% of median 680 365 81.2
2010 4,368 13th lowest of 14 · 118% of median 833 351 84.2
2011 2,524 3rd lowest of 14 · 68% of median 953 251 16.2
2012 3,363 6th lowest of 14 · 91% of median 293 319 15.0
2013 4,229 12th lowest of 14 · 115% of median 611 254 84.3
2014 4,047 11th lowest of 14 · 110% of median 737 189 60.5
2015 3,224 4th lowest of 14 · 88% of median 569 344 31.3
2016 4,015 10th lowest of 14 · 109% of median 1,088 347 71.3
2017 5,071 14th lowest of 14 · 138% of median 649 365 103.0
2018 3,914 9th lowest of 14 · 106% of median 602 365 68.6
2019 3,564 7th lowest of 14 · 97% of median 992 365 81.7
2020 3,237 5th lowest of 14 · 88% of median 1,909 305 25.7
2021 1 1st lowest of 14 · 0% of median 2,379 1 0.5
2024 — no recorded volume 856 0 —
2025 52 2nd lowest of 14 · 1% of median 764 5 11.3

How good is our record of it?

Grade A (9/10 points) — the components below are the finding; the letter alone is not.

The rubric, component by component
CheckStateDetail
identity complete name, type, and water source all on file
decreed rights on file 12 right(s), seniority decoded
diversion record current 5044 measured days, newest 360 day(s) before the data's end (DWR publishes ~1 year in arrears)
record continuity patchy 47% of the irrigation seasons in 1976-2025 carry measured days
published-record stability stable no upstream revisions recorded against this structure

Advisory reading aid on public data — not an administrative or legal conclusion, not a title opinion, and not a substitute for DWR administration or an engineer's analysis. Methodology review status is disclosed at hydrohistorian's basin pages.

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